Plasma levels of Von Willebrand factor are increased in patients with hypertrophic cardiomyopathy

Hypertrophic cardiomyopathy (HCM) is characterised by inappropriate hypertrophy, small-vessel coronary artery disease, myocyte disarray and increased interstitial fibrosis. Microvascular dysfunction is a common finding in HCM and its extent has been proposed as an important prognostic marker. Plasma von Willebrand factor (vWf) is an established marker of endothelial damage or dysfunction; however it has scarcely been studied in HCM. We hypothesised that vWf could be raised in patients with HCM and be related to different variables associated with severity of HCM.MethodsWe included 124 HCM patients, 93 males, aged 48 ± 15 years, 59 healthy control subjects with similar age and sex and 20 patients with ischemic heart disease but clinical stability for the last 6 months. A complete history and clinical examination was performed, including 12-lead electrocardiogram, echocardiography, 24 hours ECG-Holter monitoring, and symptom limited treadmill exercise test. Risk factors for sudden death were evaluated. A blinded cardiac MRI was performed with late enhanced study with Gadolinium. Plasma vWf levels were assayed by commercial ELISA.ResultsPatients showed higher levels of vWf (140.0 ± 65.0 UI/ml vs 105.0 ± 51.0 UI/ml, p < 0.001) even after adjusting for ABO blood group. vWf levels were found raised in patients with severe functional class (168.4 ± 65.9 UI/mL vs 132.4 ± 60.7 UI/mL, p = 0.020), atrial fibrillation (175.8 ± 69.4 UI/mL vs 133.0 ± 59.0 UI/mL, p = 0.005), hypertension (161.4 ± 60.8 vs 128.9 ± 60.5, p = 0.010) obstruction (153.9 ± 67.9 vs 128.2 ± 57.4 UI/mL, p = 0.046) and non sustained ventricular tachycardia (159.3 ± 59.1 vs 133.0 ± 63.0, p = 0.049). vWf correlated with age (r:0.26; p = 0.006) and obstruction (r:0.22; p = 0.021).ConclusionsWe show, for the first time, patients with HCM present significantly raised levels of vWf. These are associated with different conditions related to the severity of the disease.